A large number of different types of panels and systems of panels for covering boundaries of a room, leaving a space between the system of panel and the solid boundary of the room for accommodation of installations such as light armatures, heating or air-conditioning installations, etc. are well-known within the art. As a typical example of such systems of panels, a suspended ceiling could be mentioned.
In the present context it would be relevant to subdivide panels used for such systems into two different classes: (1) panels formed as a single body of a sufficiently rigid material and (2) panels formed by a rigid frame, over which a relatively thin sheet of material is suspended, the sheet thus forming the major portion of the surface of the panel.
Relating to the first of the above classes, EP 0 979 908 A2 discloses a ceiling panel and a system of such panels, where the panels are unitary pieces of a material of a suitable rigidity, as for instance mineral fibre, fibreglass, wood, metal, plastic, etc. and where typical dimensions of the panels are approximately 60 cm×60 cm. The edge regions of the panels are provided with laterally extending kerfs, extending into the material of the panels, for releasable engagement with a suspending structure of rails hung from the ceiling above the panels. When one or more panels have to be removed, for instance to provide access to installations above the panels, each panel is released from its engagement with the rails and removed entirely from the ceiling.
Panels and a system of such panels bearing some resemblance with the above-mentioned system of panels is disclosed in US 2003/0182894 A1. The panels according to the latter system are also hung from a system of rails attached to the ceiling above, these rails being in engagement with longitudinally extending grooves formed along the edge portions of the panels in such a manner that a given panel can be removed from the system by lifting one longitudinal edge portion hereof from the corresponding rail, after which the panel can also be released from the rail running along the opposite longitudinal edge portion hereof. After this the panel can be removed entirely from the system.
Examples of systems of panels, where the panels belong to the second of the above classes, are disclosed in the following documents:
GB 1 001 485 thus discloses systems of panels where the panels comprise a rigid frame to be supported on a system of grids for instance as a suspended ceiling. The document focuses on the attachment of a film of flexible material to the surrounding frame and in order to obtain a reliable and durable attachment of the film to the frame the edge portions of the film are made thicker and provided with an inwardly facing groove for engagement with a similar flange-like protrusion running along the outer edge of the frame. Due to the resiliency of the film, the film can be stretched over the frame and held in place by the tension in the film.
EP 0 855 477 discloses a system of panels forming a suspended ceiling, where the panels are hung from a system of rails attached to the ceiling. The system of rails provides for the possibility to move the panels from an upper level, where the panels form a closed surface to a lower level, where access can be obtained to the space between the panels and the ceiling. In order to move the panels from the upper to the lower level, the panels have to be lifted from the supporting rail system and displaced laterally, after which they can be lowered to the lower level and displaced parallel under those adjacent panels still left in the tipper level. Thus, movement from the upper to the lower level requires a series of operations, i.e. the lifting of panels followed by a transversal movement taking place above the upper level followed by lowering of the panels to the second level and finally a transversal movement in the opposite direction relative to the first transversal movement in order to bring the panels to rest on attachment means at the lower level of the system.
U.S. Pat. No. 6,499,262 B1 discloses panels for use in a suspended ceiling, the panels comprising a rigid frame over which a thin fabric can be stretched and attached to the frame. In addition to the fabric, the panels disclosed in this document also comprise various layers of material introduced to provide acoustic damping effect and to reduce acoustic transmission through the panel. The fabric is attached to the frame by tucking the fabric into a crevice formed between the main body of the frame and a resilient leg portion pressing against the main body. The leg portion and the adjacent part of the main body of the frame is furthermore provided with a pattern of teeth for attaining a secure grip on the fabric introduced between the main body and the leg. During mounting of the fabric, the fabric can be tucked into said crevice by means of a thin blade or putty knife, which can also be applied for subsequent removal of the fabric, although it is also possible to remove the fabric simply by pulling in it with a sufficient force.